I think that's a good shortcut. Converting from axis-angle to quaternions is similar to switching from an angle to a vector (cos angle, sin angle). However I di

I think that's a good shortcut. Converting from axis-angle to quaternions is similar to switching from an angle to a vector (cos angle, sin angle). However I didn't really grok quaternions until looking at geometric algebra, and I haven't used them since then so I can't be sure my intuition is right.